Novel fan blade of a ceiling fan

ABSTRACT

The present invention relates to novel fan blade of a ceiling fan, wherein whole or partial perimeter of the blades was designed to project outwardly, for example, the cross section of the outwardly perimeter of the fan blade can be presented in a shape of circular arc, oval, taper with circular arc, obliquity with circular arc, truncated taper, truncated oblique or taper with circular arc in which two sides of the projecting base have a raised bench. A comparison test showed that, the rotational speed and air volume of the novel fan blade according to the present invention is 15-24% and 5-10% greater than those of the traditional fan blades respectively, therefore resulting in saving of materials and energy.

FIELD OF THE UTILITY MODEL

The present invention relates to a ceiling fan, in particular to a novelfan blade of the ceiling fan.

BACKGROUND OF UTILITY MODEL

A conventional ceiling fan, especially decorative ceiling fan, has 4-6fan blades, each blade structure comprises a fan blade and a mountingbracket to which one end of the fan blade is locked to a motor; ifnecessary, the fan blade may be directly mounted to the motor, withoutuse of the mounted bracket. In general, each of the fan blades may bemade from wood plates, plywood or fiberboard by means of the woodworkingmachines. The perimeter of thus processed fan blade is substantiallyperpendicular to two sides surfaces of the fan blade except for beingchamfered in ordinary processing. Such a processing method is still usedup to now.

To save energy, the inventor analyzed and studied the traditional fanblades. The results showed that the resistance of such a traditional fanblade relative to the relative wind is higher and is increased withincreasing of the power of the ceiling fan and the thickness of the fanblade. To achieve the aim of saving the energy, some novel blades mustbe designed to decrease the air resistance of the fan blades.

SUMMARY OF THE UTILITY MODEL

It is an object of the present invention to provide a novel fan blade ofa ceiling fan. Such a blade not only can decrease the air resistance butalso save the energy significantly. Furthermore, the appearance of theblades is embellished. In addition, the production technique of thetraditional fan blades can be kept unchanged.

The novel fan blade according to the present invention which comprises(1) A fan blade; and (2) A mounting bracket to which one end of the fanblade is mounted and by which the fan blade is locked to a motor; ifnecessary, the fan blade may be directly mounted to the motor,characterized in that whole or partial perimeter of the fan blade ismade in an outwardly projecting shape. For example, as seen from thecross section of the fan blade, perimeter of the fan blade can bepresented in a shape of circular arc, oval, taper with circular arc,obliquity with circular arc, truncated taper, truncated oblique or taperwith circular arc in which two sides of the projecting base have araised bench.

As whole or partial perimeter of the fan blade according the presentinvention is designed to project outwardly, firstly, its weight isreduced compared to the traditional fan blades. Secondly, the airresistance is decreased. Thirdly, the appearance of the fan blade isembellished.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood from the followingdetailed description of the preferred embodiments, when taken inconnection the accompanying drawings, in which:

FIG. 1 shows a side view of a commercially available decorative ceilingfan;

FIG. 2 shows a top view of a fan blade of commercially availabledecorative ceiling fan;

FIG. 3 shows a perspective view of a mounting bracket by which the fanblade is locked to a motor of a ceiling fan;

FIG. 4 shows a transverse sectional view of the fan blade taken on lineA1-A1 of FIG.2;

FIG. 5 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the circular arc shape according to thepresent invention;

FIG. 6 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the shape of taper with arc according tothe present invention;

FIG. 7 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the shape of obliquity with circular arcaccording to the present invention;

FIG. 8 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the truncated taper shape according to thepresent invention;

FIG. 9 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the truncated oblique shape according tothe present invention; and

FIG. 10 shows a transverse sectional view of the outwardly projectingperimeter of the fan blade in the shape of taper with circular arc inwhich two sides of projecting base have a raised bench according to thepresent invention.

EXAMPLES

Referring to FIG. 1, a commercially available decorative ceiling fan isshown, including the fan blade 10, a mounting bracket 12 to which thefan blade is mounted and a motor 14. The mounting bracket 12 is mountedto the motor 14. As shown in FIG. 2, there are the through holes at oneend of the fan blade 10 for connecting the mounting bracket 12 in amanner of riveting. Referring to FIG. 3, the mounting bracket 12 isprovided with a plurality of holes in response to the through holes ofthe fan blade and the holes on the motor so that the fan blade 10 ismounted to the mounting bracket 12 and then to the motor 14.

The commercially available decorative ceiling fan blades are simpleplate structure, which has been used for long time. As shown in FIG. 4,outer of the fan blade perimeter basically is perpendicular to two sidesof the fan blade, and the corner thereof is required to be chamferedaccording to technical requirements during processing. However, suchchamfer is not able to attain the same effect as that produced by thefan blade according to the present invention.

In the traditional production technique of the fan blades, the techniqueincludes the following steps, if they are constructed of fiberboard from3 mm to 6 mm thickness:

-   1. Sticking a wood grain paper of over both sides of the fiberboard;-   2. Making rough cutting according to the required fan blade shape;-   3. Carrying out edge milling of cutting edges;-   4. Drilling through holes at one end of the fan blade;-   5. Base-coating, edge sealing, lacquering the milled edges; and-   6. Balance Weighting, matching and packing (for 5 ceiling fan    blades, the weight difference thereamong must be less than 2 g)

The fan blades of the present invention can be manufactured using theabove technique. However, in the step 3, carrying out edge milling needsto use some special milling cutters with different shapes in response tothe different outwardly projecting perimeters of the fan blades.

For example, the cross section of the outwardly projecting perimeter ofthe fan blade 101 in accordance with the present invention can be formedinto the circular arc shape by means of milling cutter in the circulararc shape, as shown in FIG. 5, wherein the radius of the circular arc(R1) is 1.0-5.0 mm. Similarly, the cross section of the outwardlyprojecting perimeter of the fan blade 102 can be formed into the shapeof taper with circular arc or oval shape by means of milling cutter withcorresponding shape, as shown in FIG. 6, wherein the radius of thecircular arc (R2) is 1-5 mm, and the taper angle (α1)is 10-60 degree,preferably 25 degree. The cross section of the outwardly projectingperimeter of the fan blade 103 can be formed into the shape of obliquitywith circular arc by means of milling cutter with corresponding shape,as shown in FIG. 7, wherein the radius of the circular arc (R3) is 1-5mm, the obliquity (α2) is 10-60 degree, preferably 25 degree. The crosssection of the outwardly projecting perimeter of the fan blade 104 canbe made into truncated taper shape by means of milling cutter withcorresponding shape, as shown in FIG. 8, wherein the taper angle (α3) is10-60 degree, preferably 25 degree, the truncated width (W1) is 1-5 mm,preferably 3 mm. The cross section of the outwardly projecting perimeterof the fan blade 105 can be made into truncated oblique shape by meansof milling cutter with corresponding shape, as shown in FIG. 9, whereinthe obliquity (α4) is 10-60 degree, preferably 25 degree, the truncatedwidth (W2) is 1-5 mm, preferably 3 mm. The cross section of theoutwardly projecting perimeter of the fan blade 106 can be formed intothe shape of taper with circular arc by means of milling cutter withcorresponding shape, as shown in FIG. 10, wherein the radius of thecircular arc (R4) is 1-5 mm, the taper angle (α5) is 10-60 degree,preferably 25 degree; while two sides of the projecting base have araised bench (d), the height of which is 0.01-2 mm, preferably 0.05 mm.

The fan blades, of course, can also be made of wood plates, plywood,decorative fiberboard or other complex wooden board or plastic or otherresin materials. The production techniques of fan blades from woodplates, plywood, decorative fiberboard or other complex wooden board arethe same as that described above, for except the plastic fan blades. Thefan blades are made from the plastic or resin material by injectionmolding technique in the art, wherein the different shapes of theoutwardly projecting perimeter of the fan blades depend on the differentshapes of the corresponding moulds.

Lastly, a comparison test between the ceiling fans with the fan bladesaccording to the present invention (group A) and with the traditionalfan blades (group B) at the same conditions.

The comparison test results show that:

-   1. The ceiling fan (group A) may increase the rotational speed which    is 15-24% greater than that of the traditional ceiling fan (group    B); and-   2. The ceiling fan (group A) may have an increased air volume which    is 5-10% greater than that of the traditional ceiling fan (group B).

The above comparison test results is enough to prove that, to achieverotational speed and air volume of the traditional ceiling fan, theceiling fan employing the fan blades in accordance with the presentinvention may select a lower power motor so that consumption of energyand/or raw materials can be reduced.

Although above preferred embodiment have been described in great detail,for those skilled in the art, changes and modifications may be madewithout departing the general design idea and the present inventiveconcept. Such changes and modifications shall fall within the scope ofthe present invention.

1. A fan blade structure for a ceiling fan comprising: A fan blade; andA mounting bracket to which one end of the fan blade is mounted and bywhich the fan blade is locked to a motor; if necessary, the fan blademay be directly mounted to the motor, characterized in that whole orpartial perimeter of the fan blade is made in an outwardly projectingshape.
 2. The fan blade of claim 1, wherein the cross section of theoutwardly projecting perimeter of the fan blade is in circular arcshape.
 3. The fan blade of claim 2, wherein that the radius of thecircular arc (R1) is 1.0-5.0 mm.
 4. The fan blade of claim 1, whereinthe cross section of the outwardly projecting perimeter of the fan bladeis in the shape of taper with circular arc or in oval shape.
 5. The fanblade of claim 4, wherein the radius of the circular arc (R2) is 1-5 mm,and the taper angle (a1) is 10-60 degree, preferably 25 degree.
 6. Thefan blade of claim 1, wherein the cross section of the outwardlyprojecting perimeter of the fan blade is in the shape of obliquity withcircular arc.
 7. The fan blade of claim 6, wherein the radius of thecircular arc (R3) is 1-5 mm, the obliquity (α2) is 10-60 degree,preferably 25 degree.
 8. The fan blade of claim 1, wherein the crosssection of the outwardly projecting perimeter of the fan blade is in thetruncated taper shape.
 9. The fan blade of claim 8, wherein that thetaper angle (α3) is 10-60 degree, and the truncated width W1 is 1-5 mm,preferably 3 mm.
 10. The fan blade of claim 1, wherein that the crosssection of the outwardly projecting perimeter of the fan blade is in thetruncated oblique shape.
 11. The fan blade of claim 10, wherein theobliquity (α4) is 10-60 degree, and the truncated width (W2) is 1-5 mm,preferably 3 mm.
 12. The fan blade of claim 4, wherein the cross sectionof the outwardly projecting perimeter of the fan blade is in the shapeof taper with circular arc, in which the radius of the circular arc (R4)is 1-5 mm, and the taper angle (αS) is 10-60 degree, preferably 25degree; two sides of the projecting base have a raised bench (d)respectively, the height of which is 0.01-2 mm, preferably d is 0.05 mm.13. The fan blade of claim 1, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 14. The fan blade of claim 2, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials. 15.The fan blade of claim 3, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 16. The fan blade of claim 4, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials. 17.The fan blade of claim 5, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 18. The fan blade of claim 6, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials. 19.The fan blade of claim 7, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 20. The fan blade of claim 8, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials. 21.The fan blade of claim 9, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 22. The fan blade of claim 10, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials. 23.The fan blade of claim 11, wherein the fan blades are made of woodplates, plywood, decorative fiberboard or other complex wooden board, orplastic or other resin materials.
 24. The fan blade of claim 12, whereinthe fan blades are made of wood plates, plywood, decorative fiberboardor other complex wooden board, or plastic or other resin materials.